Hundreds of officers travelled to Haiti to begin a UN-backed mission to curtail the influence of the country’s gangs.

A group of Kenyan police officers have arrived in Haiti, marking the beginning of a United Nations-backed mission to combat powerful armed gangs that have wreaked turmoil in the Caribbean country.

Waving Kenyan flags and sporting camouflage uniforms and rifles, several hundred Kenyan police officers stepped onto the tarmac at the Toussaint Louverture international airport on Tuesday near the capital of Port-au-Prince. More than 80 percent of the city has fallen under the control of gangs.

“I commend — and am deeply grateful to — all the countries that have pledged personnel and financial support to this mission,” United States President Joe Biden said in a statement on Tuesday, noting that the US also provided $360m in support.

While the UN has urged the international community to send a security force to Haiti, a long and controversial history of foreign interventions has caused critics to question the initiative.

Those doubts have been exacerbated by a lack of concrete details regarding the goals and actions of the latest mission.

“What is going to happen vis-a-vis the gangs?” said Romain Le Cour Grandmaison, a senior expert at the Global Initiative Against Transnational Organized Crime. “Is it a static mission? Is it a moving mission? All those details are still missing, and I think it’s about time that there’s actually transparency.”

Haitian Prime Minister Garry Conille, however, praised the effort in remarks earlier on Tuesday.

“The country is going through very difficult times,” he said. “We’re going to start working little by little to retake the country.”

Conille was named to his post last month as part of a transitional government in Haiti. The country has not held federal elections since before the assassination of President Jovenal Moise in 2021.

Speaking alongside Conille was Monica Juma, a security adviser to Kenyan President William Ruto. Juma said in remarks that the forces will serve as “agents of peace, of stability, of hope”.

However, on the day Kenyan forces arrived in Haiti, police in the Kenyan capital of Nairobi opened fire on protesters attempting to storm parliament, killing several demonstrators and injuring dozens more.

“The police should be able to operate well in their own country, but they can’t,” said Enock Alumasi Makanga, an ex-Kenyan police officer now working in private security. “How do you think they can manage then when they arrive in Haiti?”

Responding to questions about the incident, Biden administration spokesperson Matthew Miller said that the US and other countries have “vetted the Kenyan personnel” in Haiti and underscored the importance of human rights.

The Kenyan police are the first contingent of an international force in Haiti that is anticipated to reach about 2,500 police from 15 other countries.

A previous UN mission, which lasted from 2004 until 2017, did little to improve the conditions on the island. Instead, its presence was tarnished by allegations of sexual assault and the start of a cholera outbreak that killed an estimated 10,000 people.

In the intervening years, however, gangs have increased their influence, filling the power vacuum left by Haiti’s government. So far this year, violence has displaced a record 578,074 people from their homes, and nearly half of the country’s population is living with severe hunger.